InventoryScript: better syntax checking for json stream

lib/ansible/inventory/script.py

@@ -84,10 +84,14 @@ class InventoryScript(object):
 
             if not isinstance(data, dict):
                 data = {'hosts': data}
+            # is not those subkeys, then simplified syntax, host with vars
             elif not any(k in data for k in ('hosts','vars')):
                 data = {'hosts': [group_name], 'vars': data}
 
             if 'hosts' in data:
+                if not isinstance(data['hosts'], list):
+                    raise errors.AnsibleError("You defined a group \"%s\" with bad "
+                        "data for the host list:\n %s" % (group_name, data))
 
                 for hostname in data['hosts']:
                     if not hostname in all_hosts:
@@ -96,6 +100,10 @@ class InventoryScript(object):
                     group.add_host(host)
 
             if 'vars' in data:
+                if not isinstance(data['vars'], dict):
+                    raise errors.AnsibleError("You defined a group \"%s\" with bad "
+                        "data for variables:\n %s" % (group_name, data))
+
                 for k, v in data['vars'].iteritems():
                     if group.name == all.name:
                         all.set_variable(k, v)